Field of the Invention
The present disclosure relates to a cell, and in particular to a cell having an electrode group covered by two covers.
Description of the Related Art
In general, cells such as prismatic cells are widely used in electronic devices. Recently, large prismatic cells have been used in vehicles, such as electric vehicles or hybrid electric vehicles, for all or a portion of their motive power.
A conventional prismatic cell A1 is illustrated in FIG. 1. The large prismatic cell A1 includes a housing A10, an electrode group A20, a top cover A30, and outer electrodes A40. The electrode group A20 is disposed in the housing A10 via an opening A11 of the housing A10. However, the housing A10 is formed as a single piece by an aluminum extrusion process or a stamping process. Since the electrode group A20 is completely located in the housing A10, the opening A11 is very deep. Therefore, the manufacturing of the housing A10 is difficult when the prismatic cell A1 is large in size.
The top cover A30 is for covering the opening A11. Before the top cover A30 is fixed at the housing A10, flexible conductive straps A21 are manually connected to the electrode tabs A22 of the electrode group A20 and the outer electrodes A40 at the top cover A30 by manual. Therefore, the manufacturing time of the prismatic cell A1 is increased.
Furthermore, if the cell capacity of the prismatic cell A1 is increased for design requirements, the thickness of the electrode group A20 increases accordingly. The new housing A10 and top cover A30 with new specifications are required to be manufactured. Therefore, the manufacturing costs of the prismatic cells A1 with different cell capacities are increased.